1. Genetic Engineering
STS Biology
Unit 4 Genetics
Mrs. Stein

2. What is Genetic Engineering?
Manipulating DNA for practical purposes:
– DNA sequencing and the Human Genome
– Transgenic organisms have many applications
in agriculture
– DNA fingerprinting used in forensics

3. Genetic Engineering Tools: PCR
Polymerase chain reaction (PCR) uses DNA
polymerase to make many copies of DNA
Gives scientists enough DNA to work with!

4. Genetic Engineering Tools:
Restriction Enzymes
Proteins which
recognize and cut
specific base sequences
in DNA
Results in fragments of
DNA with “sticky ends”
First step in many DNA
manipulations

5. Plasmids
Plasmids – circular DNA molecules in many
bacteria

6. Plasmid use in genetic engineering

7. Recombinant DNA and Plasmids
Genes are “spliced” into plasmids
Recombinant DNA –contains DNA from
different sources
Plasmids containing the target gene are
reproduced (cloned) inside bacteria
Used to make various proteins:
– insulin, human growth hormone, pest resistance
proteins in plants

8. Gel Electrophoresis
DNA digested by
restriction enzymes Power source
Longer DNA
fragments
Shorter DNA
fragments
DNA fragments Gel
are placed in
DNA is negatively
wells of the gel
charged so it will migrate
to the positive size

9. DNA Fingerprinting
Analysis of gel
electrophoresis to
compare the genomes of
organisms
Used in crime
investigations and
paternity tests

10. Whose kids are these???
Using the gel, determine:
– Which child/children are
the offspring of both mom
and dad?
– Which child/children are
the dad’s child from
another marriage?
– Which child/children are
the dad’s child from
another marriage?
– Which child/children are
adopted?

11. Transgenic Organisms
Organisms containing genes
from other species
Transgenic bacteria produce
growth hormone
Transgenic plants and
animals improving
agriculture

12. Cloning
Making a genetically
identical organism
Potential to use
cloning to treat a
variety of disease

13. How was Dolly the sheep made?
Donor Nucleus
Cells are
fused
Fused Cell
Egg Cell
Nucleus is
removed from
the egg cell
Embryo
Cloned Lamb Foster Mother